FDA panel turns down Arcalyst use in gout

More safety data needed after Regeneron’s drug linked to increased risk of cancer

Regeneron was dealt a blow yesterday after a US Food and Drug Administration (FDA) advisory committee voted unanimously not to recommend approval of its Arcalyst product to help manage patients with gout.

The panel said that Regeneron had not provided enough safety data to show that the benefits of Arcalyst (rilonacept) outweighed its risks when used to prevent gout flares in patients starting uric acid-lowering therapy for the disease.

Gout is a painful condition that occurs when uric acid crystals are deposited in the joints and soft tissues, and affects between 5 and 6m people in the US.

Approval in this setting could transform the sales potential of Arcalyst, which has been indicated for a rare group of inherited auto-inflammatory diseases called the cryopyrin-associated periodic syndromes (CAPS) since 2008. yet brought in only around $20m last year.

Analysts have suggested in the past that Arcalyst could add $150m-$200m to its revenues if Regeneron can secure a gout indication.

The panel's 11-to-zero vote came on the back of FDA reviewer documents which suggested the agency was concerned about an increased risk of malignancy compared to placebo in Regeneron's gout trials.

Arcalyst was linked to six cases of malignancies in trials, including prostate and breast cancers, and the FDA concluded that the drug was associated with a 1 in 244 risk of developing cancer.

The company is seeking approval for the interleukin-1 (IL-1) inhibitor drug only for the first 16 weeks of uric acid-lowering therapy with allopurinol, as an alternative to current flare-preventing agents such as colchicine and non-steroidal anti-inflammatory drugs (NSAIDs) which can have significant side effects.

Panellists suggested that there could be a role for Arcalyst in gout, but that additional information would be needed to identify specific patient groups with the most favourable risk:benefit ratio.

There were also suggestions that the pharma company should carry out a longer clinical study to gauge risk, as patients may end up using it for longer than 16 weeks.

Regeneron said in a statement that it was disappointed with the vote, but would discuss the project with the FDA ahead of the agency's decision deadline of July 30.